====== Setup external hard drive ======

You should choose an external hard drive that will spin down automatically after idle(no I/O activity) for some time. And in order to let it idle, you need to dismount the drive; that leads to the use of **''autofs''**.

===== Configure autofs =====
Add this to ''/etc/auto.master'':
<code>
# dismount after no file access for 120 seconds:
/mnt /etc/auto.mnt --timeout=120
</code>

Create file ''etc/auto.mnt'' with this:
<code>
usbhd -fstype=ext3,rw :/dev/disk/by-label/USB40G
</code>

Add thsi line to ''/etc/nsswitch.conf'':
<code>
automount:     files
</code>

Restart autofs to take effect.

After that, whenever you access ''/mnt/usbhd'', the partition labeled ''USB40G'' will be auto mounted.


----

<note>The following is for something that needs the usb drive always online.</note>

===== Setup persistent storage =====

First, **don't use autofs for the drive**.

==== Label the drive ====
<code>
tune2fs -L "USB1TB" /dev/sda1
</code>

==== Update /etc/fstab ====
<code>
/dev/disk/by-label/USB1TB /mnt/usbhd ext3 defaults,noauto,relatime,data=ordered 0 0
</code>

<note>Use **noauto** or not???</note>
==== Set udev rule ====
Add these line to ''/etc/udev/rules.d/mount-usb.rules'':
<code>
ENV{ID_FS_LABEL}=="USB1TB", ACTION=="add", RUN+="/usr/local/bin/usbhd_added.sh"
ENV{ID_FS_LABEL}=="USB1TB", ACTION=="remove", RUN+="/bin/umount /mnt/usbhd", RUN+="/bin/touch /var/tmp/usbhd_removed"
</code>

Create file ''/usr/local/bin/usbhd_added.sh'':
<code>
cat > /usr/local/bin/usbhd_added.sh <<EOT
#!/bin/sh

/bin/mount /mnt/usbhd

# restart services that broke after usbhd removed and inserted again
if [ -f /var/tmp/usbhd_removed ] ; then

        /bin/rm -f /var/tmp/usbhd_removed

        /usr/sbin/service minidlna restart
        
        # more services here
fi
EOT

chmod 755 /usr/local/bin/usbhd_added.sh
</code>

So, whenever the drive is plugged, it is mounted automatically, and dependent services are restarted as needed.